نتایج جستجو برای: catalyst free reaction

تعداد نتایج: 924748  

Nanomagnetite-Fe3O4 is used as a highly efficient, mild, green and recyclable nanomagnetite catalyst for the synthesis of 4,4´-(arylmethylene)-bis(3-methyl-1-phenyl-1H-pyrazol-5-ol) derivatives in solvent-free conditions. The condensation reaction of 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one with aromatic aldehydes affords the title compounds in high yields and short reaction times. The nanocataly...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه رازی - پژوهشکده علوم 1388

heteropoly acids (hpa) and their salts have advantages as catalysts which make them both economically and environmentally attractive, strong br?nsted acidity, exhibiting fast reversible multi-electron redox transformations under rather mild conditions, very high solubility in polar solvents, fairly high thermal stability in the solid states, and efficient oxidizing ability, so that they are imp...

Journal: :iranian journal of catalysis 0
chandrakant bhenki department of chemistry, rajaram college, kolhapur 416004, india. shrikrishna karhale department of chemistry, rajaram college, kolhapur 416004, india. vasant helavi department of chemistry, rajaram college, kolhapur 416004, india.

a water soluble, bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst was used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. cost-effectiveness, use of non-hazardous solvents, metal free and commercially available catalyst, single-step, environmentally friendly gre...

Journal: :journal of chemical health risks 0
farhad hatamjafari department of chemistry, faculty of science, islamic azad university, tonekabon branch, tonekabon, iran

the present study aimed to use a method for the synthesis of some 3, 4-dihydropyrimidin-2-(1h) - ones/thiones. the study tried to answer the question whether this reaction can be performed without solvent and with new catalyst or not. to find answer to the question, we described a novel protocol for the efficient synthesis of 3, 4-dihydropyrimidin-2-(1h)-one derivatives using aromatic aldehyde,...

Journal: :iranian journal of catalysis 2015
leila moradi gholam reza najafi hakimeh saeidiroshan

multiwalled carbon nanotubes (mwcnts) have been functionalized with -so3h groups using new three steps chemical routes. firstly, oh groups have been attached to cnt surfaces through a radical reaction. the second step involves converting the hydroxyl groups into the oxide one and last step included the attachment of –so3h groups on the mwcnts surfaces in the presence of 1-butyl-3-methyl imidazo...

Journal: :iranian journal of catalysis 2015
abdolkarim zare fereshteh abi vahid khakyzadeh ahmad reza moosavi-zare alireza hasaninejad

nanomagnetite-fe3o4 is used as a highly efficient, mild, green and recyclable nanomagnetite catalyst for the synthesis of 4,4´-(arylmethylene)-bis(3-methyl-1-phenyl-1h-pyrazol-5-ol) derivatives in solvent-free conditions. the condensation reaction of 3-methyl-1-phenyl-1h-pyrazol-5(4h)-one with aromatic aldehydes affords the title compounds in high yields and short reaction times. the nanocataly...

Journal: :iranian journal of catalysis 2015
mahdieh chegeni ardeshier khazaei sadegh rahmati mohammad hossein fekri

in this report, synthesis, characterization and application of silica perchloric acid nanosphere as a novel and heterogeneous catalyst is described. these nanospheres have been characterized by xrd, ft-ir, bet and tga spectra and also by sem and tem images. the results show that it has a spherical shape and the particles size are between 75 and 100 nm. the catalytic activity has been investigat...

Journal: :organic chemistry research 0
mehrnoosh kangani department of chemistry, university of sistan and baluchestan, p.o. box 98135 – 674, zahedan, iran nourallah hazeri department of chemistry, faculty of sciences, university of sistan and baluchestan, zahedan 98135-674, iran malek taher maghsoodlou department of chemistry, university of sistan and baluchestan, p.o. box 98135 – 674, zahedan, iran ali ebrahimi department of chemistry, university of sistan and baluchestan, p.o. box 98135 – 674, zahedan, iran

cellulose was applied as a reusable and green catalyst for the facile four-component synthesis of 6-amino-4-aryl-3-methyl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile derivatives using hydrazine monohydrate, ethyl acetoacetate, malononitrile and aryl aldehydes, under solvent-free and thermal conditions. the use of non-toxic and inexpensive catalyst, short reaction time, clean work-up and goo...

Sulfonic acid functionalized nanoporous silica (SBA-Pr-SO3H) with a pore size of 6 nm catalyzed three component coupling of aromatic aldehydes, urea and ethyl acetoacetate to afford the corresponding dihydropyrimidinones under solvent free condition. This new protocol for Biginelli reaction has important advantages such as green synthesis, short reaction time, easy isolation and high yields of ...

Ali Reza Badiei Ghodsi Mohammadi Ziarani, Mahbobeh Haddadpour Yeganeh Khaniania

Sulfonic acid functionalized SBA-15 (SBA-Pr-SO3H) as a new nanoporous acid catalyst was used in the one-pot synthesis of polyhydroquinolines derivatives via the Hantzsch four component condensation reaction of aldehydes, b-ketoesters, dimedone and ammonium acetate under solvent free conditions with short reaction time in excellent yields. SBA-P...

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